The Cell Sciences and Immunochemistry Core (CIC) is an integral part of the SLE SCOR Center, providing services to the four principal investigators on projects that rely on the following laboratory support. First, routine histology and electron microscopy studies and their interpretations. Second, tissue and cellular localization of antigenic molecules by immunohistology, and messenger RNA (mRNA) by in situ hybridization. Third, acquisition and management of human and murine recombinant proteins and peptide libraries for the "lupus antigens" including Ro60, Ro52, La, Sm, calreticulin, U1-70 RNAP, dsDNA and phospholipids. Fourth acquisition and management of a library of essential monoclonal Ab and cDNA probes for Ag localization and flow cytometry, as well as B cell hybridomas generating sufficient monoclonal Ab for in vivo experiments. Fifth, quantitation and isotype determination of human and murine autoAb by immunoprecipitation and ELISA. Sixth, quantitation of murine cytokines by ELISA. The CIC will function, in collaboration with the project investigators, in experiments that: 1) analyze autoAb responses to the "lupus Ag" and their overlapping peptides, 2) require peptides for mapping their T and B cell epitopes, 3) evaluate the immunopathologic end points including the detection and semi-quantitation glomerulonephritis, sialoadenitis and diseases affecting other organs that result from autoimmune response to the lupus Ag, 4) evaluate the quality of the autoimmune response with respect to the specificity and Ig isotype of the autoAb and the nature of the cytokines produces by peptide specific T cells. In summary, the CIC will support the research project of the SLE SCOR by providing common reagents and by conducting several essential and common techniques.